Study On Ni-catalyzed Three-component Dicarbofunctionalization Of Unbiased Alkenes

Transition metal-catalyzed dicarbofunctionalization of alkenes could construct complex functional molecules from readily accessible feedstocks rapidly by simultaneously assembling two different carbon entities across alkene molecules in one single operation.However,most of them are limited to conjugated alkenes or tethered alkenes.There are a few reports on catalytic three-component intermolecular dicarbofunctionalization of unbiased alkenes.Particularly,enantioselective control of the stereogenic centers formed in three-component assembly mode remains a formidable challenge.To address this challenge,this thesis focus on nickel-catalyzed three-component dicarbofunctionalization of unbiased alkenes taking advantages of weak chelation groups.Part I: A series of chiral bisoxazoline ligands bearing different side chains have been designed and synthesized for precise control of the electrical properties,steric hindrance and other factors of bisoxazoline ligands.Using(R,R)-4-iHeptyl-Bi Ox,we developed the first enantioselective three-component carbo-arylation of unbiased alkenes with(hetero)aryl halides and perfluoroalkyl iodides through nickel-catalyzed cross-electrophile coupling for the construction of a broad scope of chiral β-fluoroalkyl arylalkanes with excellent enantioselectivity.Part II: Based on nickel metal and bisoxazoline catalytic system,selective threecomponent reductive carbo-vinylation of unbiased alkenes has been developed by using perfluoroalkyl iodides as radical precursor,alkenyl halides as coupling partner and manganese as reductant.The benign protocol could tolerants a wide range of functionalized of alkenes and alkenyl halides for the construction of various β-fluoroalkylalkenyl compounds with moderate to excellent yields.A wide range of functional groups,such as ketones,esters,amides,imines,ethers,carbamides,carbonates,and sulfones could serve as the weak directing groups in this protocol.Part III: A mild catalytic system of nickel catalyst and chiral oxazoline ligand for asymmetrical reductive three-component alkylalkenylation of allyl ketone with cis-alkenyl iodides and perfluoroalkyl iodides was developed,providing a diverse range of synthetic valuable enantioenriched β-alkenyl ketones.In this protocol,five-membered nickellacycles formed via pendant β-ketone group plays a crucial role for enantioselective control of the stereogenic carbon center adjacent to an alkenyl group.